1. Field of the Invention
The present invention relates to optical receiver modules that receive optical signals, and to methods and control programs for reception of optical signals.
The present application claims priority on Japanese Patent Application No. 2010-118841, the content of which is incorporated herein by reference.
2. Description of the Related Art
Patent Document 1 discloses an optical dispersion compensating device including a variable dispersion compensator, a bit error information generator and a controller, which is designed to perform automatic compensation on polarized dispersion of optical signals.
Patent Document 2 discloses another optical dispersion compensating device including a variable dispersion compensator, a bit error information monitor and a controller.
Patent Document 1: Japanese Patent Application Publication No. 2002-208892
Patent Document 2: Japanese Patent Application Publication No. 2009-177237
These technologies are unable to properly search for optimum points in transmission lines susceptible to polarized dispersion of optical signals. This is because signal quality greatly varies due to polarized states in transmission lines susceptible to polarized dispersion of optical signals. Polarized dispersion may lead to erroneous detection of optimum dispersion compensating values due to polarized states; hence, it is very difficult to optimally perform dispersion compensation on optical signals.